Many proteins have been studied extensively at the single molecule level. However, in the cell those proteins form into larger complexes or modules wherein the spacing of components on a nanometer scale is critical. New technologies in patterning and stamping now enable us to systematically measure the dependence of interactions on nanometer level patterns and to then exploit that spatial dependence in sensing and nanofabrication of materials through directed self-assembly. As an example, the signals from extracellular matrices affect normal and cancerous cell growth and there is evidence that the spacing of the matrix molecules makes a critical difference in that signal (Jiang, G. et al. (2003) Nature, 424:334-37). These mechanisms must be studied at a scale that matches the size and/or spacing of features of specific protein or subcellular protein complexes, which are generally at the nanometer level.
There is a great need to measure the binding of complex protein assemblies with spatially ordered ligands. Thus, there is a great need for a device that tests the binding of an analyte to specific spatial arrays of ligands.